Interlock



' Jan. 11, 1944. K, HUGHES 2,338,943

INTERLOCK Driginal Filed Aug. 25, 1938 Daniel K. Hughes Inventor His Attorney Patented Jan. 11, 1944 INTERLOCK Daniel K. Hughes, Dayton, Ohio, assignor to The National Cash Register Company, Dayton, Ohio, a corporation of Maryland Original application August 25, 1938, Serial No. 226,690. Divided and this application August 20, 1941, Serial No. 407,665

4 Claims.

This invention relates to cash registers and more particularly to means for insuring that a printing operation which has been begun will be completed,

This application is a division of the application for Letters Patent .of the United States, Serial No. 226,690, which was filed by Daniel K. Hughes on August 25, 1938, and which issued on October 6, 1942, as United States Patent No. 2,297,961.

In cash registers of the type to which the instant invention is applied, impression mechanism is shiftable from a normal or home position to a position opposite one or another of a plurality of sets of type wheels to print amounts therefrom. To insure that an impression will be made whenever the impression mechanism is shifted from home position, a set of levers are set when the impression mechanism is moved from home position and prevent the impression mechanism from being restored tohome position unless the levers are reset by an impression being made.

It is an object of the invention, therefore, to

provide means to compel the completion of any printing operation when it is once initiated.

A further object of the invention is to prevent the impression mechanism from being restored to home position, When it is moved therefrom to take an impression from type, until after the impression is actually made.

With these and incidental objects in view, the invention includes certain novel features of construction and combinations of parts, the essential elements of which are set forth in appended claims and a preferred form or embodiment of which is hereinafter described with reference to the drawing which accompanies and forms a part of this specification.

In the drawing:

Fig. 1 is a vertical section from front to rear through the middle portion of theprinting mechanism as viewed from the left.

Fig. 2 is a detail showing the mechanism for forcing a complete operation of the printing mechanism before it may be returned to home position.

Fig. 3 is a detail showing, in moved or blocking position, the mechanism for forcing a complete operation of the printing mechanism before the printing mechanism can be returned to home position.

General description The machine in whichthe instant invention is embodied is provided with three sets of printing wheels, one of said sets of wheels being detail printing wheels which are set according to the amounts of entries and the other two sets of printing wheels forming totalizers which may accumulate totals of the amounts of the entries and from which these totals may be printed.

In order that the various amounts may be printed, a rockable frame containing a platen, record material, and a ribbon is provided. This frame normally occupies a position in which the platen is opposite the detail printing wheels, and during every amount entry the platen is operated to print the amount on the record material. When it is desired to print a total from either of the totalizers, the frame is rocked from its home position to bring the platen, the record material, and the ribbon opposite the selected totalizer and to operate the platen to print the total on the record strip. To prevent any misoperation of the machine and to insure that a printing operation from a totalizer, once begun, will be completed, a system of levers is provided, which levers are moved to blocking position when the frame is rocked from its home position and block the return of the frame until the levers are restored from blocking position by the platenoperating means during a printing operation of the platen. It is this system of levers, their setting to blocking position, and their restoration, with which this invention is concerned.

Detailed description Only those details of the detail printer, the totaliz er, the actuating means therefor, and the printing means which are necessary for an understanding of the instant invention will be described herein. For further details of these mechanisms, reference may behad to Patent No. 2,297,961, of which this application is a division.

Frame for supporting the detail printer and the totalizers Mounted on a cross member 5! and a shaft 11 are a right printing Wheel support frame plate 18 (Fig. 1) and a left frame plate (not shown), which arefspaced by appropriate rods and shafts. The side plates are secured to flanges (not shown) projecting from a rear plate 303.

Detail printer The detail printer includes a plurality of type wheels D (Fig. 1), which are settable according to entered amounts and which are rotatably carried by a shaft 83 supported by the printing wheel support frame plates.

Totalz'zers 85 and 86 are carried by rockable framesmot shown) mounted in the printing wheel support frame plates before mentioned.

Printing mechanism Rockably mounted on cross member 53 (Fig. 1) by claws I85 is the printer frame consisting of a right frame plate It Il and a left frame plate (not shown) spaced apart and secured by rods I02, I63, and I84 so as to form a supporting frame for the printing mechanism.

In normal position, the center of gravity of the printer frame and the mechanism which it supports is to the rear of and above cross member 5|, causing the frame to stay rocked rearwardly, where it is supported on a portion of the rear frame plate (Fig. 1) serving this purpose.

In printing transaction data from the detail printing wheels onto the record strip, the printer frame is not moved from its normal position, as the platen is then directly over the printing line of said wheels.

When printing transactions from either the I or the 11" totalizer printing wheels, the printer frame is rocked forward to one of two positions, determined by stops, so as to position the platen H5 to take an impression from the I totalizer wheels or the II totalizer wheels, as selected by manipulative means to be hereinafter described.

On the left side of the right frame plate I86 of the printer frame (Fig. 1) is a stud ISI, on which is pivotally mounted a printing hammer I62.having a normal position in which it rests onthe upper edge of the horizontal arm of a bell crank lever I63, which is also pivotally mounted on stud IGI. Bell crank lever I63 and the printing'hammer not being in the same plane, the forward or striking portion of the hammer has welded to it an extra width of metal to bring it into the plane of bell-crank I33, upon which it rests, said extra width of metal serving the additional purpose of weighting the hammer. Bell crank lever M3 is urged normally counter-clockwise by springs I 3 3 and 1&5 against a portion of frame I Ilil, an offset bearing edge I66 being provided on the downwardly-extending arm of bellcrank IE3 for that purpose. Bell crank I83 thusmay be moved clockwise only, against the force of springs I54- and 165. This movement of bell crank lever I53 occurs each machine operation through a cam IE1 secured on a drive shaft 3%, which engages a roller stud I68 on the bell, crank lever I63, forcing it clockwise. At approximately the middle of the operating cycle, the cam I 51 presents an abrupt break allowing the springs I64 and I55 to pull the bell crank lever Hi3 sharply counter-clockwise to its stopping point. Hammer I52 is likewise carried counter-clockwise, but continues moving under its own momentum after bell crank lever I63 has been stopped.

Inasmuch as means for rotating the drive shaft 35 forms no part of the instant invention, this means will not be described in detail herein. Reference may be had tothe above-mentioned United States Patent No. 2,297,961 for these details.

Platen I I5 (Fig. 1) is mounted in a frame I69 pivotally mounted on rod I I4 journaled in the printer frames. Clutched by a tongue-andgroove connection to the frame I69 is a rearwardly-extending arm I10, the under side of the rear end of which arm is adapted to be struck by the hammer I62, causing the platen to carry a record strip against the printing wheels. The forward end of arm I10 has a thumb piece by which the arm may be moved on rod II4 to the right, unclutching the arm from the frame I69. The thumb piece is normally held to the left, in which position frame I69 and arm I10 move as a unit.

Attached on the inside of printer frame I00 is a shield I (Fig. 1) preventing the operator from holding the rear end of arm I10 so it will be unaffected by the hammer blow.

Spring I1I normally holds the platen slightly away from the printing wheels by holding the rear end of arm I10 against stud I12. A bentover portion I13 of lever I31 locks the platen against printing movement unless lever I31 has been rocked in a printing operation.

The printer frame also carries record material supporting and feeding mechanism and a ribbon supply mechanism. These mechanisms will not be described herein, as they are not essential to an understanding of the instant invention. Reference may be had to the above-mentioned United States Patent No. 2,297,961 for details of these mechanisms if such details are desired.

As shown in Fig. 1, the record material I05, in its movement from a supply roll (not shown) to a storage roll (not shown), passes over the rods I03 and II 4, thence around the platen H5, and back over the rods H4 and IE3.

The platen I I5 (Fig. 1) is normally over the detail printer wheels on shaft 83 so as to be in proper position on each machine operation to print the amount involved in the transaction.

On total-taking operations, the platen and the record material must be moved so as to be over the I or the II totalizer. This is accomplished by rocking the printer frame forward around cross member 5! until the platen is over the selected totalizer.

As the cam I61 rotates only during a machine operation in which an impression is taken from the detail printer, other means is provided for actuating the hammer in total-printing operations which involve no rotation of shaft 35.

If the operator wishes to print from the I totalizer, lever I31 (Fig. 1) is grasped by the handle I18 and drawn forward and downward, which rocks the printer frame and associated parts around cross member 5i. When lever I31 is manually rocked clockwise, shoulder I14 engages pawl I15 pivotally mounted on hammer 152 by stud I16 and normally held clockwise by a spring against an adjustable screw stop I11, causing further clockwise rocking of lever I31 to rock hammer I52 clockwise against the action of springs I64 and I 65. Due to the distance between centers I36 and IIiI, the shoulder I14 will eventually slide over pawl I15, allowing the springs I64 and Hi5 to cause the hammer to strike the platen a blow. On the return counterclockwise rocking of lever I31, shoulder I14 by-passes pawl I15, causing it to rock counter-clockwise as viewed in Fig. 1. During the operation of the lever I31, a stud I19 extending fromlever I31. enters. cam slot I88 in the right printing wheel supportplate 18; which slot is so shaped that lever I31 is rocked slightly clockwise with relation to-the printer frame and cocks the hammer. The hammer is released as stud I19 reaches the bottom of the slot. The stud engaging the bottom of. the slot I 88 also positions the printer frame so that the platen will be over the I counter.

If the operator wishes to print from the II counter, the printer frame is drawn forward by the handle I88; which causes stud I19 to enter cam slot I89 in the right printing wheel. support plate 18 and allowsthe printer to rock forward until the platen is over the II counter. This cam slot is also formed so as to cook the hammer and release it as stud I19 reaches the bottom of the slot. In drawing the printer forward by handle I18, lever I31 moves slightly before the printer starts, thus causing stud I19 to enter slot I80 instead of slot I89, which it enters when handle I88 is used.

As lever I31 is drawn forward by handle I18, a bracket I9I (Fig. 2 attached thereto is interposed between arm I-18 and frame plate I98, preventing the shifting of arm I18 to the right to disable the platen.

Device preventing incomplete total-printing operation- One of the novel features of the invention is a device which prevents the printer frame from being returned to home position, after being therefrom, unless a complete total-taking operation is performed, thus requiring an impression to be taken from the selected totalizer. This device prevents the operator from manipulating the printer in such a manner that a totalizer might be reset without an impression of the amount standing thereon being first taken.

Mounted on the left of printer frame I08 (Figs. 1, 2, and 3) are two levers I59 and I58, which are pivotedv on studs I6I and I68. These levers are normally in the position shown in Fig. 2 when the printer frame is in home position, with the lever I59 resting against the rear frame plate 303. When the printer frame is rocked forward, spring I51 (Fig. 2) tends to rotate the levers I59 and I58 each clockwise as seen in Fig. 2, the lever I59 rotating to the position shown in Fig. 3, and the lever I58 rotating so that the rear part of lever I58 engages notch I56 in the periphery of lever I59, to latch lever I59 in moved position and prevent. the

printer frame from being returned to home position, as the rear end of lever I59 will then strike the rear frame plate 383 before the printer frame reaches home position. During the rocking of the printer "frame forward, the stud I19 (Fig. 1), as explained, will enter either cam slot I80 or I89, rocking lever I31 clockwise in relation to the printer frame as viewed in Fig. 1. As the rocking of lever I31 occurs before the lever I59 has moved to bring notch I56 opposite the rear part of the lever I58, the stud 9| on lever I31 will be out of the path of lever I58 as the lever turns clockwise on stud I60 to enter into latching engagement with the notch I56. The notch 90 in lever I58 accommodates stud 9I during the remainder of the forward operation of the lever I31. Levers I58 and I59 remain engaged until the lever I31 has actuated the printing hammer and until the return movement of lever I 31, which, in by-passing bell crank lever Lil I15; rocks the bell crank. lever I 15 counterclockwise, as viewed: in Fig. 3, to the position shown in dot-and-dash outline in this figure, so that the upper extendingarm of the bell crank I15 strikes the forward extending part I55 of lever I58 and rocks this lever clockwise, as viewed in Fig. 3, to the position shown in dotand-dash outline, in which position lever I58 is out of latching engagement with notch I56, and out of the path of stud 9| as lever I31 moves home. When lever I31 returns to home position, stud III is positioned over lever I58 and prevents this lever from engaging notch I56. When the lever I58 is moved out of latching relation with notch I56, lever I59 can be rotated clockwise as viewed in Fig. 1 and counterclockwise as viewed in Fig. 2 by the movement of the printer frame, which is now allowed to return to home position.

Automatic hammer adjustment In the instant machine, printing from the detail printing wheels involves only five characters, printing from either totalizer involves seven characters, and; provision has been made for causing the hammer to strike a more. forceful blow when printing a total from the I or the II totalizer than it does when printing the transactions from the detail printing wheels on registering operations. This mechanism will now be described.

Springs I64 and I65 are attached at their rear ends to the bell crank lever I63. The front end of spring IE5 is attached to stud I8I on the right printer frame I80. The front end of spring I64 is attached to stud I82 on a lever I83 pivoted on stud I84 extending from the right frame IIIII of the printer. Secured to the right side of the right printing wheel support frame 18 is a cam I85 which guides a roller I86 mounted on a downwardly-extending arm of lever I83. As the printer frame is rocked forward for total taking, the roller I88 travels along cam I85, stretching spring I64. On total-printing operations involving either the I or the II totalizer, the roller reaches the surface I81, which is arcuate, having cross member 5I as a center, thus causing the hammer blows on the "1 and on the II totalizers to be of the same force.

It is believed that the operation of various mechanisms described above, and particularly the interlock for preventing the return of the printing frame to home or normal position until after a printing impression has been made, is clear from the above description, and no further description of the operation of these mechanisms is necessary.

While the form of mechanism herein shown and described is admirably adapted to fulfill the objects primarily stated, it is to be understood that it is not intended to confine the invention to the one form or embodiment herein disclosed, for it is susceptible of embodiment in various forms all coming within the scope of the claims which follow.

What is claimed is:

1. In a machine of the class described, the combination of a printer platen shiftable from a normal home position to another position in which an impression is to be made; means to actuate the platen to cause an impression to be made when the platen is in said other position; a pair of levers shiftable with the platen as the platen moves from home position; means for moving one of said levers to blocking position as it is shifted with the platen and for moving the other of said levers to latch said one lever in blocking position to prevent the return of the platen to normal home position; and means on said other lever engageable by said actuating means, after the platen has been actuated, to unlatch said one lever to allow it to be moved from blocking position when the platen is shifted to its normal home position. v

2. In a machine of the class described, the combination of a plurality of sets of type wheels; a platen; a frame supporting said platen, said frame being rockable from a home position to bring the platen selectively opposite various ones of said sets of printing wheels; means carried by the frame and movable from a normal position to actuate the platen after the platen has been positioned opposite a set of type wheels; a plurality of cooperating levers carried by the frame, one of said levers being movable to blocking position to prevent the return movement of the frame to home position and the other of said levers being movable to latch said one lever in blocking position; means to move said one lever to blocking position as the frame moves from home position and to move said other lever to latching position; means on the actuating means for preventing the latching movement of said other lever until the actuating means has moved out of home position to actuate the platen; and means on said other lever engageable by the actuating means, as it returns to home position after actuating the platen, for shifting said other lever out of latching position to allow the one lever to be moved out of blocking position and enable the frame to be returned to home position. 3. In a machine of the class described, the combination of a plurality of sets of type wheels; a platen; a frame supporting said platen,said frame being rockable from a home position to bring the platen selectively opposite various ones of said sets of wheels; platen operating means; a printing hammer for operating said platen to take impressions from said type wheels and a lever, carried by said frame, rockable relative thereto, and operable, as the frame is moved from home position to bring the platen opposite any selected one of said sets of wheels, for causing the operation of said hammer means; a blocking lever carried by said frame and normally out of blocking position; means for moving the blocking lever to blocking position as the frame is moved from home position; a retaining lever engageable with said blocking lever to retain the blocking lever in blocking position to prevent the return movement of the frame to home position; means on said first-mentioned lever for holding the retaining lever out of retaining engagement with the blocking lever until the first-mentioned lever has rocked relative to the frame; and means on the retaining lever by which the retaining lever can be moved by the platen operating means to release the blocking lever as the first-mentioned lever is returned after causing the operation of the hammer, the operation of the blocking lever being such that it will prevent the return of the printing frame to home position until after the platen has been operated.

4. In a machine of the class described, the combination of a machine frame member; a plurality of sets of type wheels; a platen; a printer frame for supporting said platen, said printer frame being normally in home position where a portion thereof engages the machine frame, but rockable from said home position to bring the platen opposite selected ones of said sets of type wheels; platen operating means including a hammer for actuating the platen to take impressions from the selected sets of type wheels, and a lever, carried by said frame, rockable relative thereto, and operable, as the frame is moved from home position to bring the platen opposite the selected set of type wheels, to cause an operation of the hammer; a blocking lever pivotally carried by the printer frame at a point adjacent where it engages the machine frame, said blocking lever having a notch therein and being normally within the printer frame and out of blocking position; means to move the blocking lever from within the printer frame as the printer frame moves from its home position, said blocking lever moving to a position where it will engage the machine frame member and block the return of the printer frame to home position; a retaining lever pivotally carried by the printer frame and having a shoulder movable into engagement with the notch in the blocking pawl to retain the blocking pawl in blocking position; means on said first-mentioned lever cooperating with the retaining lever to prevent the engagement of the shoulder with the notch on the blocking lever until the first-mentioned lever is moved when the printer frame moves from home position; and means on the retaining lever by which the retaining lever can be moved by the platen operating meansto remove the shoulder from the notch on the blocking lever as said first-mentioned lever is returned with the printer frame to home position, whereby to allow said blocking lever to be moved within said printer frame and enable the printer frame to be returned to home position.

DANIEL K. HUGHES.

CERTIFICATE or CORRECTION. Patent No. 2,553,915. January 11, 19th.

DANIEL K. HUGHES.

of the above numbered patent requiring correction as follows: Page A, first column, line l l, claim 5, after "means"" strike out the semi-colon and I insert instead --inclucli ng--; and that the said Letters Patent should be read with this oorrectl on therein that the same may conform to the record of the case in the Patent Offi ce.

Signed and sealed this ll th day of March, A. D. 19%.,

Leslie Frazer '(Seal) Acting Commissioner of Patents. 

